Automatic spark timer



March l2', 1929. C. STOKES 1,705,316

AUTOMATIC SPARK TIMER Filed Nov- 24, 1925 IN VEN TOR.

Patented Mar. 12, 1929i.

UNITED STATES CHARLES LAWRENCE STOKES, OF LOS ANGELES, CALIFORNIA.

AUTOMATIC SPARK TIMER.

Application filed November 24, 1923. Serial No. 676,863.

My invention relates to improvements for advancing, or retarding,'the time of applying the ignition spark to a mixture of fuel and air in the cylinder of an internal combustion engine.

y The principal object of my invention is to automatically advance and retard the spark, thereby obtaining maximum power and maximum economy for all speeds, or loads, of an internal combustion engine.

A further object yof my invention is to automatically control said spark according to the presure generated by the oil pump of an internal combustion engine.

Referring to the drawings in which the same numbers indicate like parts Fig. 1 is a view of the apparatus as applied to a spark distributor.

Fig. 2 is a sectional view along the lines A-A of Fig. 1.

,The ignition spark for an internal combustion engine is generally controlled by a -tiiiici' 1, wherein the spark is diverted to the cylinders of an internal combustion engine through any desired number of cables. a t tached to any desired number of plugs 2 1n timer housing 1. The timerA 1 may be 0f any wellknown make and is driven by suitable mechanism from some part of the engine which it serves in the -usual manner, and the advance, or retardation, of the timer 1 is accomplished by means of a lever 3 through the manual control of a rod 4 which is held in a known, it is not deemed necesary to show the specific parts thereof, because such are not herein claimed and my apparatus, which is to be further described, may beeasily applied to any well known timer.

A second rod 6 is fastened by one end to the lever 3 through a second hole 7 and the rod 6 is threaded at its other end to be firmly fastened to a rod 8 and vheld therein by a locknut 9.

vThe actuation of the lever 3 is caused by themovement of a diaphragm, or bellows 11 by means of the rod 8 which is securely fastened to a cover 10 soldered to one end of the bellows 11, thereby making 11 fluid ltight at one end.

A casing 13 is closed at one end by a cover casing is held by means of screws 16 to the crankcase 17 of an internal combustion engine, or the casing 13 may be attached to any other suitable portion of said engine.

11 is soldered interiorly of the casing 13 and has its open end approximately concentric with the open end of said casing so that there may be a free movement of the rod 8 through said open en'd of 11.

The structure as described leaves an annular space 20 between thewalls of the bellows 11 and the casing 13 and to this space 2() a pipe 18 is led from the discharge side of the engine oil pump (not shown), and' a pipe 19 leads from 20 to the interior of the crankcase 17, or any other desired part of the engine.

'Ihe operation is as follows The oil pump of an interior combustion engine is generally driven from the engine crankshaft by suitable means to the end that the suction, or oil pressure, developed by the 011 pump varies in proportion with the increase, or decrease, of the speed of the engine. If now it be assumed that oil pressure is being applied from the oil pump through 18 to 20, the same pressure for any predetermined speed will cause the rods 8 and 6 to advance the timer 1 a predetermined degree of angularit'y, because the pressure of the oil in the Space 20 will cause a of the bellows 11.

When the engine is'stopped the bellows 11 compression l will expand to a position where the spark will be at the right position for starting the engine, it being noted that the oil under pressure will pass continuously from the space 20 through the pipe 19 to the interior of the crank case 17 so that the bellows 11y may expand through the cessation of the oil pressure applied thereto.

The construction of the bellows `11 is such that it permits the rod 8 to have a universal motion so that shocks, misplacements, etc. do not effect the advancing, or retarding, of the bellows 1. At the saine time, an adjustment is provided by having the rod 6 screwbe had. A similar effect on the bellows 11 is Acaused by the operation of the oil pump suc- 14 which is pressed therein. The casing 13 \.be desirab e to close off 19 entirely and proisy provided with a flange .1 5 whereby said Vide suitable bell crank motion invbetween threaded into rodl 8 thereby allowing ,any initial and final position of the lever 3 to the rod 6 and lever 3, for advancing or retarding the timer 1.

The diaphragm 11 is formed as a bellows and being made of metal the same act-s as a spring to be compressed by the oil pressure and returns to a normal position on the cessation of the pressure.

It is to be noted that when the engine is cold, the viscosity of the oil will be at a maximum, therefore pressure will build up in the space 20 to a maximum Jfor all speeds. Thus, immediately after starting, or idling speeds, a good advance of the timer 1 is attained, which is desirable because the ex- 15 plosion time in the engine cylinder is protracted at low temperatures. Thereafter, as the engine warms up and the viscosity of the oil lowers, the oil pressure at the same speed will be lowered to normal and the position of the timer 1 will be automatically adjusted for the explosion time of a hot mixture of fuel and air to be tired.

My preferred application of the invention embodies the use of the voil pressure developed by the engine lubrication pump, but the suction developed by said pump vis also effective for the purpose described. In each case a pressure generated from the oi`l pump is the source'of power used for actuating my apparatus, in one case positive pressure is employed and in the other case a negative pressure is employed, but as alreadystated I prefer the application of a positive pressure, which is caused by the oil pump sucking oil from a sump on the interior of the crankcase 17 and circulating the same under pressure through the casing 13.

`I claim:

1. In a timer control mechanism, the combination of a easing, a bellows within said l casing, the interior of said bellows being open to the atmosphere, an adjustable rod secured to the bottom of said bellows and havingits free end provided with means for directly connecting said rod to said lever, apipe for delivering lubricating oil to the space between said bellows and the walls of said easing, and a pipe for removing the oil from said casing.

2. In a timer control mechanism, the combination of a casing having an opening therein, a compressible, resilient bellows having substantial depth in said casing, one end of the said bellows being closed and the other end open to the atmosphere and secured around the edge of said opening, and an attaching member connected to the closed end of said bellows and extending outwardly through said opening and adapted to be connected to a timer.

3. A timing control mechanism for internal combustion engines comprising a fluid-tight casing having anopening there-V0 in, a compressible, resilient bellows member in said casing, a rigid member connected to said bellows and extending outwardly through said opening and adapted to be connected directly to a timer lever, a conduit for conducting lubricating oil to said casing for compressing said bellows for operating said lever for advancing the spark, and a conduit for conducting said Huid from said casing.

Signed at Wilmington, in the county of Los Angeles and State of California, this 16th day of'November, A. D. 1923.

CHARLES LAWRENCE STOKES.

CERTIFICATE 0F CORRECTION.

Patent No. l, 705, 316.

Granted March l2, 1929, to y CHARLES LAWRENCE sToKEs.

It is hereby certified that error appears in the. printed specification of the above numbered patent requiring correction as follows: Page 2,l line 45, claim 1, before the word ,"lever" insert the word "timer"; and that the said ,Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 23rd day of April, A D. 1929.

(Seal) M. J. Moore, Acting Commissioner of Patents.

CERTIFICATE 0F CQRRECTION.

Patent No. 1,705,316. y Granted March 12, 1929, to

CHARLES LAWRENCE STOKES. It is hereby eertified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 2, line 45, claim 1, before the were! "lever" insert the Word "timer"; and that the said Letters f Patent should be read with this correction therein that the same may conform to the record of the case in the Patent (ffiee.

Signed and sealed this 23rd day of April, A. D. 1929.

M. J. Moore, Acting Commissioner of Patents.

(Seal) 

